Official Luthiers Forum!

Hi gang,

I am currently building guitar #3 and am currently at the stage of gluing
the headblock. I would like to see pics or tips of how you all accomplish
this task as I'm looking for a consistent method to use.

For #1 I used the Cumpiano method and glued the blocks to the top.
On #2 I used a mold from our good friend John Hall. The problem with
this is the area of the neck block in the mold is curved which caused me
(and Carlton)! quite a bit of sanding the rim to get back to flat.

John, bless his heart, tried to explain to me his method but it left me
scratching my head.
I know some folks clamp and glue their headblock outside the mold.
I'm having a hard time understanding how you get both sides and the
block lined up perfectly, add cauls and clamp without everything moving
with only two hands?

Finally, just one more question pertaining to the neckblock.
If you place the neckblock topside down on your work surface, shouldn't
the face that glues to the side read a true 90 degrees?
Mine seems to be a few degrees greater than 90.

Thanks for all your help...
PS. I spent a great deal of time searching the archive to no avail before
resubmitting a question I'm sure has been answered before.

_________________
Christopher C. Cordle
North Muskegon, MI

http://www.yardsaleunderwear.com
http://www.facebook.com/christopher.cordle

Thanks for the visuals Hesh....

Any comment on the 90 degree question I posed?

Also, for keeping things lined up... keeping the sides flat with weight is a
good idea...I have a 6 x 18 slab of marble that should work nicely..
do you take one side and clamp it to the block then bring the other side to
meet it and clamp it?

Thanks,
Chris

_________________
Christopher C. Cordle
North Muskegon, MI

http://www.yardsaleunderwear.com
http://www.facebook.com/christopher.cordle

Thanks hesh,

I am using Watkins necks & blocks so yes, you answered my question...
but leads me to the next one

since one side of the block is obviously longer than the other, is it the front
edge of the block that would sit flush with the top edge of the side?
Does this question even make sense? I don't remember this being an issue
on #2

_________________
Christopher C. Cordle
North Muskegon, MI

http://www.yardsaleunderwear.com
http://www.facebook.com/christopher.cordle

Great thread Hesh, thank you!

One last question...I think

You say you do not radius your upper transverse graft...
(I did it this way this time for the first time), isn't that going to cause a slight
dilemma when placing the top on as the headblock will have a slight arch
but the upper bout of the body will be flat in this area?

Man, you truly are a great resource

_________________
Christopher C. Cordle
North Muskegon, MI

http://www.yardsaleunderwear.com
http://www.facebook.com/christopher.cordle

[QUOTE=Hesh1956] Chris this is another great question and again the
answer has to do with the "system" that you use to build with.

True I don't radius the upper transverse brace or the popsicle brace if I
use one. These braces are sanded flat.

Prior to installing the top and after the top of the rim is radiused I do this:

Put sand paper on a flat surface, self stick on a bench top is fine but I use
a 24" X 24" flat 3/4" plywood board for this. Make pencil marks on the
top of the neck block and the kerfing all the back to the center of the
waist.

Place the rim face down on the flat board with sand paper on it (pencil
marks on block and kerfing are now in contact or nearly in contact with
the sand paper).

Use a 1/8" shim or stick under the tail block and move the upper bout
back and forth, side to side, on the sand paper until all of the pencil
marks are gone.

This flattens the upper bout of the face of the rim to now match the
upper bout of the top with no radius in the transverse braces.

Some additional notes: The flat upper transverse brace, popsicle brace,
and sound hole supports are glued on in the go-bar deck but not in the
dish, on a flat board again.

I have used this system with OMs, d****n****ts, L-OOs, and OLF SJs with
25' and 28' top radiuses and it works great. For other top radiuses it may
not work as well in as much as the neck set-back angle and bridge height
are very much a function of the radius used on the top.

The real reason that I use this system is to ensure no hump or drop off of
the fret board at the neck/body joint.

Any way my friend this flattens out the upper bout for the non-radiused
top.
[/QUOTE]

Ok, then...at this point, haven't you essentially completely flattened out
the backset angle machined into the block, the 91.5 degrees you spoke of
above? And if not completely flat, I still don't see how the block can make
complete contact with the top.And if completely flat, then why not just do
it at the onset before installing? I'm obviously missing something here...

On #2 I radiused the upper transverse brace and was still able to remove
the 14th fret hump by sanding the fretboard level before fretting.
This was the first time I've tried it with the flat transverse and I'm finding
it a tad confusing.

_________________
Christopher C. Cordle
North Muskegon, MI

http://www.yardsaleunderwear.com
http://www.facebook.com/christopher.cordle

[QUOTE=Hesh1956] Nope you are not flattening the top of the neck
block at all.

Since the rim is face down with the tail block elevated/shimmed 1/8" it all
works out to almost exactly the 91.5 degrees or what ever it is that
comes on the block.

The difference is that the radius across the block from dish sanding is
now gone. It's a near if not perfect match and the top makes full contact
with the entire top of the block.

If you were to look at the rim from the side face down on a flat surface
with the tail elevated 1/8" you will see the angle that is sanded into the
neck block top. I wish I had some pictures of this process to show you
but I don't.

[/QUOTE]

No picture necessary...your last paragraph gave me the visual I needed.
Thanks so much hesh! I think you made it through the denseness of my
gray matter

_________________
Christopher C. Cordle
North Muskegon, MI

http://www.yardsaleunderwear.com
http://www.facebook.com/christopher.cordle

[QUOTE=Hesh1956]



[/QUOTE]

StewMac clamps? Who uses Stew Mac clamps?

Great Thread

Hesh, I'll be darned - your idea of using bondo to make the radiused caul is brilliantly simple !!! As is the idea of shimming the blocks instead of wrestling with the blocks when dishing the profile